From: Jani Nikula Date: Fri, 8 Feb 2019 18:42:53 +0000 (+0200) Subject: drm/i915/opregion: rvda is relative from opregion base in opregion 2.1+ X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=a0f52c3d357af218a9c1f7cd906ab70426176a1a;p=openwrt%2Fstaging%2Fblogic.git drm/i915/opregion: rvda is relative from opregion base in opregion 2.1+ Starting from opregion version 2.1 (roughly corresponding to ICL+) the RVDA field is relative from the beginning of opregion, not absolute address. Fix the error path while at it. v2: Make relative vs. absolute conditional on the opregion version, bumped for the purpose. Turned out there are machines relying on absolute RVDA in the wild. v3: Fix the version checks Fixes: 04ebaadb9f2d ("drm/i915/opregion: handle VBT sizes bigger than 6 KB") Cc: Ville Syrjälä Cc: Imre Deak Reviewed-by: Ville Syrjälä Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20190208184254.24123-2-jani.nikula@intel.com --- diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c index f1b841580521..5e00ee9270b5 100644 --- a/drivers/gpu/drm/i915/intel_opregion.c +++ b/drivers/gpu/drm/i915/intel_opregion.c @@ -123,7 +123,8 @@ struct opregion_asle { u64 fdss; u32 fdsp; u32 stat; - u64 rvda; /* Physical address of raw vbt data */ + u64 rvda; /* Physical (2.0) or relative from opregion (2.1+) + * address of raw VBT data. */ u32 rvds; /* Size of raw vbt data */ u8 rsvd[58]; } __packed; @@ -964,9 +965,24 @@ int intel_opregion_setup(struct drm_i915_private *dev_priv) if (opregion->header->over.major >= 2 && opregion->asle && opregion->asle->rvda && opregion->asle->rvds) { - opregion->rvda = memremap(opregion->asle->rvda, - opregion->asle->rvds, + resource_size_t rvda = opregion->asle->rvda; + + /* + * opregion 2.0: rvda is the physical VBT address. + * + * opregion 2.1+: rvda is unsigned, relative offset from + * opregion base, and should never point within opregion. + */ + if (opregion->header->over.major > 2 || + opregion->header->over.minor >= 1) { + WARN_ON(rvda < OPREGION_SIZE); + + rvda += asls; + } + + opregion->rvda = memremap(rvda, opregion->asle->rvds, MEMREMAP_WB); + vbt = opregion->rvda; vbt_size = opregion->asle->rvds; if (intel_bios_is_valid_vbt(vbt, vbt_size)) { @@ -976,6 +992,8 @@ int intel_opregion_setup(struct drm_i915_private *dev_priv) goto out; } else { DRM_DEBUG_KMS("Invalid VBT in ACPI OpRegion (RVDA)\n"); + memunmap(opregion->rvda); + opregion->rvda = NULL; } }